This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Our purpose in this project is to design an easy-to-implement scheme for fluorescence microscopy with high spatial resolution and fluorescence enhancement properties based on the resonant excitation of 2D-PhC guided modes. It is well known that the interaction of an external radiation with a periodically nanostructure such as a PhC affects the far field propagation of electromagnetic waves. In brief, the periodicity allows for phase-matching of evanescent waves in the near field region to localized leaky modes supported by the PhC. Thus, the external excitation of leaky modes is associated with a total reflection phenomenon for a resonant wavelength. However, the light does not reflect abruptly;and an illuminated region called the evanescent wave region, is present on the interface between the PhC and the medium (typically air or water) where the intensity decays exponentially from the PhC surface. Using this PhC's property and the fluorescence enhancement shown previously [Estrada et al, 2010. Optics Express, Vol. 18, Issue 4, pp. 3693-3699 (2010)] we are designing new substrates for fluorescence microscopy.